The flying saucer. For decades it's been synonymous with UFO terror. But millions of reported encounters tell a very different story. From Cold War showdowns to telepathic terrors, join is as we track the rise of Black Triangles.

Millions of people believe extraterrestrial live on Earth. Are the aliens here to enlighten us or destroy us? What if the worst-case scenario happened? What would aliens do? And how would they do it?

UFOs. They can fly at blinding speed. Or hover effortlessly just a few feet above the ground. And they can do it all without making a sound. But how is this possible? The mysteries of anti-gravity propulsion are unsealed.

Nations all over the world are rumored to have recovered metal debris from these UFO crashes. From self-healing hulls to sinister alien implants, join is as the secrets of UFO metals are UNSEALED.

Our world is home to many UFO hot spots, where unidentified objects are reported with alarming regularity. But a select few locations have something extra. They're notorious for strange paranormal phenomenon to extraterrestrial activity.

Do visitors to planet Earth come from some far off galaxy? Traveling vast distances to the only planet boasting intelligent life in this corner of space. We investigate the shocking secrets of alien civilizations in our solar system.

In 1969, the U.S. government officially announces it will stop investigating UFOs, but declassified documents reveal that multiple government agencies have been hiding important UFO sightings for decades.

Some experts believe many atmospheric light shows are actually caused by extraterrestrials. Do they pose an imminent threat to humanity? Join us as the alien secrets behind atmospheric anomalies.

They're our first line of defense in the darkest of times. And they're often the first responders to threats from another world. Over the past 70 years the world's military forces have come face to face with thousands of UFOs.

Every day, millions take to the sky in commercial flights all over the world. But decades of evidence have revealed we may not be the world's only frequent flyers. Are we in danger of losing control of our skies to extraterrestrial beings?

It's the ultimate close encounter. There have been thousands of reported cases all over the world. But these claims are almost invariably dismissed by authorities with little or no investigation.

The Nazis. Led by Adolf Hitler, they were the greatest evil the world has ever known. In just ten years, Hitler took Germany from crushing depression to world domination. Did the Nazis have access to alien technology?

Alien abductions are the only types of encounters in which eyewitness testimony can reveal details about the inside of UFOs. Details that can help us understand how aliens live and what they want from the human race.

In the 1960s we too our first steps into a vast new realm-bound for the Moon. But NASA astronauts would soon find they weren't the only ones out there.

It's the stuff of nightmares. Emergency lines flooded with calls as UFOs appear in the sky. Mounting evidence has revealed that UFO waves are able to penetrate the world's most closely guarded airspace.

Experts have long believed the universe to be riddled with mysterious portals - shortcuts through space that allow travelers to span vast distances in the blink of an eye. From mighty volcanoes to secret underground civilizations.

Many believe aliens are already here on Earth. But why are they here? Are aliens planning an all-out attack on planet Earth? And if they are, is there any way we can fight back?

Rapid advancements in science and technology have given mankind unprecedented access to distant galaxies that could harbor life. And some scientists believe that to find alien life we need look no further than our own backyard.

What are UFOs? Are they spacecraft? Do they travel vast distances to reach planet Earth? From mysterious planets at the edge of the Solar System, to epic journeys beyond the boundaries of time and space.

In order to survive mankind must find a way to navigate the galaxy. Alien encounters have offered a possible glimpse into the secrets of interstellar flight, but how would extraterrestrials know how to navigate the vast regions of space?

Do aliens exist? And have they visited planet Earth? These are perhaps the most important questions of our time. For decades, eyewitnesses have come forward with unsettling stories of alien bodies recovered from crashed UFOs.

In the spring of 1952, UFO sightings go off the charts. For years, the U.S. government has told the postwar public that UFOs do not exist, but behind the scenes, U.S. Air Force officials are divided.

Since the early 1960s, we've experimented with how to travel off planet Earth. Many experts believe America has operated a secret Space Force for decades, with ultra high-tech ships designed for missions beyond Earth's orbit.

If aliens have visited Earth, why are they here and what are they truly after? Investigations have revealed the possibility that aliens are interested in experimenting on not only the human body, but the human mind as well.

Nearly three hundred million people worldwide claim to have been abducted by aliens. Many report being subjected to torturous medical experiments. Others return with unwelcome reminders of their ordeal. Are aliens creating human hybrids?